Hello Wel come to health care magic Dear patient , some times excessive straing can cause severe headache due to rise in pressure through out the body including in the head, but i don t think it could have been any serious problem like subarachnoid haemorrhage because that could have worsened with the intake of aspirin as aspirin is a blood thinner and could have worsened subarachnoid haemorrhage. how ever if you want to seek a neurologist consultation there is nothing wrong in it , i will also suggest a consultation with an endocrinologist also because you are taking radio active iodine for graves disease and as you say that you are very anaemic, have low blood counts and have also developed constipation for which you needed to take dulcolex, may be you are developing hypothyroidism also , endocrinologist will get your thyroid profile repeated and will adjust the dose of radioactive iodine wish you good luck thanks Dr Arshad